1. Arrange rubber waterproof ring or end seal around the base plate, the advantage of this method is that the customization is stronger, and the small crushing pin and the cutting fluid with small particles can be blocked outside the base plate; 2. Protective sheet metal can be set on the periphery of the tray. The advantage of this method is that the protection ring in the inner cavity of the foundation plate can be blocked, and the spray cleaning device can be added to clean the surface of the positioner twice. 3. Can add a separate locator waterproof ring, direct protection of the locator part, more suitable for increasing the transformation on the basis of the existing, low cost;